Cooling fan and electronic device using the same

Abstract

A cooling fan includes a base, a stator and an rotator, one end of the stator is fixed to the base, the other end of the stator forms a shaft, the rotator is mounted to the shaft, an end of the shaft protrudes out of the rotator, each of the rotator and the shaft is <same as claims> an electromagnet driving unit matching each other, the rotator is driven to rotate by the electromagnet driving unit. An electronic device using such a cooling fan is further disclosed.

What is claimed is: 
     
         1 . a cooling fan, comprising:
 a base;   a stator, the stator comprising two ends, one end mounted to the base and a shaft extending from the other end; and   a rotator mounted to the shaft;   wherein an end of the shaft protrudes out of the rotator, the rotator and the shaft each having an electromagnet driving unit, and the rotator is driven to rotate by the electromagnet driving unit.   
     
     
         2 . The cooling fan of  claim 1 , wherein the rotator is rotatably mounted to the shaft, the rotator is driven by the electromagnet driving units to revolve around the shaft. 
     
     
         3 . The cooling fan of  claim 2 , wherein a coil assembly is mounted around the shaft, the coil assembly is electrically connected to a driving circuit, the rotator comprises a bearing assembly and at least one magnetic element corresponding to the coil assembly, the rotator is rotatably mounted to the shaft through the bearing assembly; when the coil assembly is powered on, the rotator is driven by the electromagnetic force of the coil assembly through the magnetic element. 
     
     
         4 . The cooling fan of  claim 3 , wherein the bearing assembly comprises a bearing sleeve and a bearing coupled in the bearing sleeve, the central portion of the rotator is fixed to the bearing sleeve, the bearing is sheathed on the shaft; the rotator and the bearing sleeve is driven by the coil assembly to rotate around the shaft. 
     
     
         5 . The cooling fan of  claim 4 , wherein the bearing sleeve and the rotator are thermally attached to each other. 
     
     
         6 . The cooling fan of  claim 3 , wherein the cooling fan further comprises a circuit board, the shaft comprises a receiving groove, the coil assembly comprises a plurality of magnetic coils received in the receiving groove, the circuit board is electrically connected to the magnetic coils and is located next to the receiving groove; the circuit board comprises a supply circuit and a control circuit, the control circuit adjusts the speed of the rotator by adjusting the number of electrified magnetic coils. 
     
     
         7 . The cooling fan of  claim 6 , wherein a magnetic conductive element is inserted in a middle portion of the coil assembly. 
     
     
         8 . The cooling fan of  claim 6 , wherein the magnetic conductive element is silicon steel sheet. 
     
     
         9 . The cooling fan of  claim 3 , wherein a peripheral portion of the rotator extends along an axial direction of the rotator and forms a flange, the magnetic element is mounted to an inner surface of the flange and corresponds to the position of the magnetic coils. 
     
     
         10 . The cooling fan of  claim 3 , wherein the magnetic element is made of permanent magnet materials. 
     
     
         11 . An electronic device comprising:
 at least one electronic component; and   a cooling fan for cooling the at least one electronic component comprising   a base;   a stator, the stator comprising two ends, one end mounted to the base and a shaft extending from the other end; and   a rotator mounted to the shaft;   wherein an end of the shaft protrudes out of the rotator, the rotator and the shaft each having an electromagnet driving unit, and the rotator is driven to rotate by the electromagnet driving unit.   
     
     
         12 . The electronic device of  claim 11 , wherein the rotator is rotatably mounted to the shaft, the rotator is driven by the electromagnet driving units to revolve around the shaft. 
     
     
         13 . The electronic device of  claim 12 , wherein a coil assembly is mounted around the shaft, the coil assembly is electrically connected to a driving circuit, the rotator comprises a bearing assembly and at least one magnetic element corresponding to the coil assembly, the rotator is rotatably mounted to the shaft through the bearing assembly; when the coil assembly is powered on, the rotator is driven by the electromagnetic force of the coil assembly through the magnetic element. 
     
     
         14 . The electronic device of  claim 13 , wherein the bearing assembly comprises a bearing sleeve and a bearing coupled in the bearing sleeve, the central portion of the rotator is fixed to the bearing sleeve, the bearing is sheathed on the shaft; the rotator and the bearing sleeve is driven by the coil assembly to rotate around the shaft. 
     
     
         15 . The electronic device of  claim 14 , wherein the bearing sleeve and the rotator are thermally attached to each other. 
     
     
         16 . The electronic device of  claim 13 , wherein the electronic device further comprises a circuit board, the shaft comprises a receiving groove, the coil assembly comprises a plurality of magnetic coils received in the receiving groove, the circuit board is electrically connected to the magnetic coils and is located next to the receiving groove; the circuit board comprises a supply circuit and a control circuit, the control circuit adjusts the speed of the rotator by adjusting the number of electrified magnetic coils. 
     
     
         17 . The electronic device of  claim 16 , wherein a magnetic conductive element is inserted in a middle portion of the coil assembly. 
     
     
         18 . The electronic device of  claim 16 , wherein the magnetic conductive element is at least one silicon steel sheet. 
     
     
         19 . The electronic device of  claim 13 , wherein a peripheral portion of the rotator extends along an axial direction of the rotator and forms a flange, the magnetic element is mounted to an inner surface of the flange and corresponds to the position of the magnetic coils. 
     
     
         20 . The electronic device of  claim 13 , wherein the magnetic element is made of permanent magnet materials.